Influence of Interaction Between Phonons on Mean Number of Polaron Phonons in Weak-coupling Quantum Dot

The properties of weak-coupling polaron are studied by using the linear combination operator and the unitary transformation methods in quantum dot.Considering the interaction between phonons of different wave vector in the recoil process,the ground state energy of polaron as a function of the confinement length of quantum dot and the mean number of phonons are discussed.Numerical calculation results showed that the ground state energy of polaron and the mean number of phonons decreased with increase of the confinement length of the quantum dot,and the mean number of phonons increased with the increase of the ground state energy of the quantum dot.When the ground state energy was held constant,the mean number of phones was less when the interaction between phones was considered than when the interaction was not considered.This showed that the influence of interaction between phonons on the mean number of phonons cannot be ignored.